Many of those commenting on the decision in Citizens United v. Federal Election Commission have focused on the power-grab part. I agree with them. It was unnecessary for the court to go so far when there were several less-radical grounds available. It was audacious to seize the opportunity to overrule precedents when the parties had not pressed this issue and the lower courts had not considered it. It was the height of activism to usurp the judgments of Congress and state legislatures about how best to prevent corruption of the political process.

"If it is not necessary to decide more, it is necessary not to decide more," a wise judge once wrote. That was Chief Justice John G. Roberts -- back when -- and dissenting Justice John Paul Stevens rightly turned that line against him.

As bad as the court's activism, though, was its shoddy scholarship.

First, the majority flung about dark warnings of "censorship" and "banned" speech as if upholding the existing rules would leave corporations and labor unions with no voice in the political process. Untrue. Under federal election law before the Supreme Court demolished it, corporations and labor unions were free to say whatever they wanted about political candidates whenever they wanted to say it. They simply were not permitted to use unlimited general treasury funds to do so. Instead, they were required to use money raised by their political action committees from employees and members. This is hardly banning speech.

Second, in the face of logic and history, the majority acted as if there could be no constitutional distinction between a corporation and a human being. Untrue. The Supreme Court has long held that corporations are considered "persons" under the Constitution and are therefore entitled to its protections. For more than a century, Congress has barred corporations from making direct contributions to political candidates, with no suggestion that it must treat corporate persons the same as real ones; that prohibition stands, at least for now. The "conceit" of corporate personhood, as Stevens called it, does not mandate absolute equivalence. That corporations enjoy free-speech protections does not mean they enjoy every protection afforded an actual person. Is a corporation entitled to vote? To run for office?

Third, misreading its precedents and cherry-picking quotations, the majority acted as if the chief case it overturned was an outlier. In that 1990 case, Austin v. Michigan Chamber of Commerce, a six-member majority came to the unsurprising conclusion that a state law prohibiting corporations from making unlimited independent expenditures from their general funds was constitutional. The court dismissed this ruling as "a significant departure from ancient First Amendment principles." Again, untrue.

In a 1982 case, the court -- in a unanimous opinion by then-Justice William Rehnquist -- noted that Congress, in writing campaign finance law, was entitled to "considerable deference" in taking into account "the particular legal and economic attributes of corporations and labor organizations" and had made "a permissible assessment of the dangers posed by those entities to the electoral process." Four years later, even as it carved out an exception for nonprofit corporations, the court reaffirmed "the need to restrict the influence of political war chests funneled through the corporate form."

The Citizens United majority relied heavily on a 1978 case overturning a Massachusetts law that prohibited corporations from spending their own money to defeat certain referendums. But that decision specifically noted that "a corporation's right to speak on issues of general public interest implies no comparable right in the quite different context of participation in a political campaign for election to public office."

Fourth, the majority bizarrely invoked the "Mr. Smith Goes to Washington" defense. Under the Austin ruling, Justice Anthony M. Kennedy argued, lawmakers unhappy with being lampooned in the movie "could have done more than discourage its distribution -- they could have banned the film." Beyond untrue. There is no scenario under which works of art about fictional lawmakers could be limited by campaign finance laws.

That the majority would stoop to this claim underscores the weakness of its case -- and the audacity of the result it has inflicted on the political process.